EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: Bronco Leonard on December 24, 2016, 07:02:35 am
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I'm building an ultrasonic varmint stay-away using a sine wave generator feeding a mid-sized, mid-quality auto power amp. My question is this: I've tried two different sig gen circuits and both make a nice sine wave, but they both have a DC offset of several volts. Will this bother the power amp, or would any reasonable amp have a dc filter built into it's input circuitry?
If I have to block the dc myself, would a simple RC filter set to 500 hz do the job?
Edit: I forgot to mention that I am using an old XR-2206 for signal generation. Does it have a built-in way to control the output offset voltage?
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You have to check the specs of the Amp to see if its DC coupled.
Most are not, but check.
You can DC offset a signal, here is one method using 2 R's, and attached a calculator
to determine their values. Notde the zip file has other stuff in it as well for other prob-
lems.
https://www.dropbox.com/s/k1yn4m7heaixvmg/ADinput%20negative%20inputs.zip?dl=0 (https://www.dropbox.com/s/k1yn4m7heaixvmg/ADinput%20negative%20inputs.zip?dl=0)
Regards, Dana.